I've not seen the DVD jacket so I'm surprised as all get out hearing Linda is pictured in Ken's/Cliff's arms. When I originally saw the episode I swore&worried all summer long Cliff had found Pam floating in that pool.
Now I can't answer your question but will say(according to what I've heard&read)tptb had tried getting rid of LG a couple of times before the season four cliffhanger. Initially the character of Sue Ellen was mere background character more or less. I've read it was Larry that spoke up for keeping Linda on. I've also heard,though I can't remember where,it was Larry that encouraged Linda to do punch up what little lines she was given in the early days of the series(now I might have it turned around a bit;could've been that LG told Larry she was going to&he agreed). I do distinctly remember reading Linda was fired around season 8 when she asked if she could direct a few episodes. Tptb reversed their decision when Larry threated to walk off the show.
Hopefully someone with a better memory than mine will come along&answer your question. I'd love to know the answer too lol.
P.S.(Here's another useless bit of tv/Dallas trivia)Mary Fran was considered for the role of Sue Ellen.I've also heard Linda Evans was in the running for the role of Pamela Ewing(some say she was first choice.)
Give me a shout out if you're ever on Jeapordy lol.